As Saturday night's strike deadline approaches for US Airways Group Inc. and its 7,000 mechanics and cleaners, there are indications other US Air employees might be inclined to support a walkout by the mechanics.

Last week, the leadership of another group of workers represented by the International Association of Machinists union, 6,200 ramp workers, pledged to honor a mechanics' strike, meaning that more than 13,000 of US Air's 40,000 employees could legally walk off the job Sunday, barring intervention by President...